ISO/NP 11943-2

Hydraulic fluid power — Online automatic particle-counting systems for liquids — Part 2: Methods of performing calibration

Scope

This document establishes methods for:
— performing on-line secondary or tertiary calibration of automatic particle counters (APCs); sizes
traceable to ISO 11171, using a hydraulic system validated in the manner described according to
ISO 11943-1
— matching two or more on-line automatic particle counters, such that the APCs installed on the
same hydraulic system count the same number of particles per mL at any size; in which at least
one of them must be calibrated according to this standard and used as a reference, using a
hydraulic system validated according to ISO 11943-1.

This document is applicable for use with hydraulic fluids, aviation and diesel fuels, engine oil and
other petroleum-based fluids.